There are many types of computing services, resources and data that computer users and applications need to manage and otherwise access. Such resources and data include services and data maintained locally, and data maintained on corporate networks and other remotely accessible sites including intranets and the internet.
The concept of web services is generally directed to providing a computing service to clients via protocols and standards that are cross-platform in nature. In general, web services provide the basic tools for wiring the nodes of a distributed application together, regardless of the type of platform on which the requesting client is running. As there are many different computing platforms, various platform-independent mechanisms and protocols that facilitate the exchange of network information are becoming commonplace in web services, including HTTP (HyperText Transfer Protocol), XML (extensible Markup Language), XML Schema, and SOAP (Simple Object Access Protocol) XML. Traditional web services, in which businesses, organizations, and other providers offer services to users and applications, are presently based on these standards. Moreover, as described in U.S. patent application Ser. No. 10/328,714, assigned to the assignee of the present invention, a web service can represent other types of resources, such as hardware devices, databases and the like.
U.S. patent application Ser. No. 10/856,399, assigned to the assignee of the present invention and herein incorporated by reference in its entirety, describes an application model a method, system and mechanism including a web services application protocol (WSAP), that, among other things, formally represents the state and behavior of a service via a port, (e.g., URI), whereby the entities in a service may be contacted directly for interaction. In other words, unlike other protocols, WSAP describes the behaviors of a web service in a formalized manner, e.g., with each behavior of a service having its own port. The WSAP protocol also facilitates the usage of intermediaries by defining shared semantics on verbs, which identify what a message is, what the processing of message is, and how it affects the state/behavior of the receiver. Further, the ordering of messages and operations provides context to what is occurring.
Given the complexities of a distributed operating system in which portions of the operating system execute on separate processors, many traditional tools do not work very well. For example, traditional stack-based debuggers are not well-suited for the message-based world of a distributed operating system, including that it is nearly impossible to set traditional breakpoints on multiple recursive copies of a service written to manipulate messages from, for example, fifty or so remote services. Furthermore, since these services are effectively black boxes, it is meaningless to “step into” or “set a breakpoint” inside a remote service running across a corporate trust boundary.